This invention relates to an electronic balance and, more particularly, to an electronic balance capable of displaying a measured weight value in any unit selected from a plurality of different units.
An electronic balance of this kind usually has a plurality of conversion formulas stored in a read-only memory for converting weight data into a plurality of units and obtains a value to be displayed by using the formula corresponding to the selected one of these units. The method of switching units or selecting one of them on such an electronic balance may be hardware-based such as the method of using dip switches and the method of providing a separate switch for each unit, or software-based such as the method of operating a menu selection key to cause the units stored in a memory device to be displayed sequentially and operating another key while the desired unit is being displayed to thereby make the selection. Although the number of selectable units are increased on such an electronic balance for improved usefulness, users in ordinary business usually do not use all of the available units. Most users tend to merely switch among a relatively small fraction of the available units.
From this perspective, let us reconsider the prior art methods of switching units described above. As the number of selectable units becomes large, the operation for switching units becomes troublesome by the method of using dip switches or a menu selection key. If separate keys are to be provided to individual units, on the other hand, an increased number of keys will be required and this results in high costs of manufacturing. Errors are likely to occur especially with the method of assigning individual keys when units are switched in a series of measurements for the same sample.
It is therefore an object of the present invention to provide an electronic balance with which the user can easily switch units or select a unit without making errors.